Page 140 of Ghostwalk says the following about the farming methods of people living in Salkiria:

Ghostwalk: Chapter 4 Countries: Salkiria wrote:In addition to the many cities, Salkiria has a large number of farming plantations and vineyards, often owned by nobles or retired wealthy merchants or musicians. Salkirians usually have small families, typically parents and two to three children, although grandparents usually live in the home as well. Those families that own large famrs and need extra hands rely on sharecroppers and migratory laborers to get the work done. Many of these moving colonies of laborers have a gypsylike mystique and have their own style of music and dancing. Salkirian halflings usually live in cities, although a few sedentary families have bought a few prosperouse vineyards and now make excellent wine in very small bottles.

Wikipedia has an article about sharecropping, but there seems to be lots of different types of sharecropping.

I've seen a few articles about medieval demographics, but they mostly focus on cities. Has anyone seen any articles about estimating the number of sharecroppers living on the land? And has anyone seen any articles about migratory farm labour, that might give me a clue about how many gypsylike Salkirians would be travelling across the land and picking crops.

I know we used to have hop-picking in the farms around London, with families having "working holidays" during the hop-picking season. Maybe Salkiria could have something like that, but what would the migratory labourers be doing the rest of the year? I know that different crops have different seasons, so maybe (and I'm not sure on the crops) there could be several months of labouring, but I'm guessing there would be some dead months when the migratory labourers would have nothing to do in the Salkirian countryside. So, what else could they be doing?

Do you think that some of they gypsylike migratory labourers might also operate the ghostwalk?